Damper and automobile seat having the damper

ABSTRACT

A damper ( 1 ) has silicone-based unvulcanized rubber ( 4 ) interposed between a housing ( 2 ) and a shaft ( 3 ) which are disposed in such a manner as to be relatively rotatable about an axis (A) in (R) directions with respect to each other, and rotational energy between the housing ( 2 ) and the shaft ( 3 ) is absorbed through the deformation of the silicone-based unvulcanized rubber ( 4 ).

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a damper for absorbing moving energybetween a pair of members disposed relatively movably with respect toeach other so as to damp the relative movement of the pair of members,as desired. More particularly, the present invention concerns a damperfor an automobile seat for absorbing the rotational energy of a rearseat of an automobile arranged to be, for example, rotatable (capable ofspringing up) so as to be able to eliminate such as a shock occurring inthe rear seat at the time of its springing up or returning, suddenspringing up of the rear seat due to sudden braking when the rear seatis unlocked, and sudden returning of the sprung-up rear seat due tosudden acceleration, as well as an automobile seat having this damper.

2. Description of the Related Art

As dampers, various dampers are known including a friction damper makinguse of sliding friction, a fluid damper making use of a fluid, a viscousdamper making use of a viscous material, and a lead damper making use oflead. However, the friction damper is accompanied by wear in conjunctionwith friction and undergoes the deterioration of its characteristicsover long periods of use. The fluid damper and the viscous damper arebound to become large in size to obtain a large damping force, andrequire seals for preventing the leakage of the fluid and the viscousmaterial. The lead damper brings about an increase in weight due tolead, and is difficult to be applied to an apparatus which needs to bemade lightweight.

In addition, as a damper for a backrest of an automobile seat, onemaking use of a fluid is known, but such a damper making use of thefluid is bound to become large in size to obtain a large damping force,and requires a large-scale seal for preventing the leakage of the fluid.In particular, in the case of the damper for an automobile seat in whicha backrest is arranged to be folded down and the seat is arranged to besubsequently sprung up in order to secure a large accommodation spacewithin the vehicle compartment, it is necessary to damp large rotationalenergy based on the total load of the backrest and the seat, so that itis difficult for a compact damper merely making use of a fluid to obtaina targeted large damping force.

SUMMARY OF THE INVENTION

Accordingly, the invention has been devised in view of theabove-described various aspects, and its object is to provide a damperwhich has no possibility of wear and makes it possible to eliminate aseal for preventing leakage and to easily obtain a large damping forceeven if the damper is lightweight and compact.

Another object of the invention is to provide a damper which makes itpossible to obtain a large damping force and can be made compact andwhich is particularly suitable for an automobile seat in which abackrest is arranged to be folded down and a seat is arranged to besubsequently sprung up, as well as an automobile seat having thisdamper.

In accordance with a first aspect of the invention, there is provided adamper comprising silicone-based unvulcanized rubber interposed betweena pair of members disposed in such a manner as to be relatively movablewith respect to each other. In accordance with a second aspect of theinvention, there is provided a damper comprising silicone-basedunvulcanized rubber interposed between a pair of members disposed insuch a manner as to be relatively movable with respect to each other,relative moving energy between the pair of members being absorbedthrough the deformation of the silicone-based unvulcanized rubber.

According to the damper in accordance with the above-described first andsecond aspects, since the damping function is arranged to be obtained bythe silicone-based unvulcanized rubber, there is no risk of wear, a sealfor preventing leakage can be omitted, and a large damping force can beeasily obtained even if the damper is lightweight and compact.

As in the damper in accordance with a third aspect of the invention, thesilicone-based unvulcanized rubber is sufficient if it has a degree ofplasticity of not less than 30 and not more than 420. Preferably,however, as in the damper in accordance with a fourth aspect of theinvention, the silicone-based unvulcanized rubber has a degree ofplasticity of not less than 60 and not more than 320. More preferably,as in the damper in accordance with a fifth aspect of the invention, thesilicone-based unvulcanized rubber has a degree of plasticity of notless than 160 and not more than 320.

The degree of plasticity in the invention is a value measured by aWilliam plastometer standardized by the American Society for Testing andMaterials (ASTM) and the like. Specifically, the silicone-basedunvulcanized rubber which has a cylindrical shape with a diameter ofapproximately 1.43 cm and a height of 1.27 cm and has a volume of 2 ccis sandwiched by two upper and lower parallel plates, and is compressedby a load of 5 kg at 70° C. to 100° C., and is pressurized for 3minutes, and the degree of plasticity is expressed by the height(mm/100) of the silicone-based unvulcanized rubber after thepressurization.

In the invention, the silicone-based unvulcanized rubber is sufficientif it has a degree of plasticity of not less than 30 and not more than420. However, if the degree of plasticity is smaller than 30, thesilicone-based unvulcanized rubber is liable to flow, and thesilicone-based unvulcanized rubber disposed between the pair of membersrequires sufficient sealing for preventing its leakage, and it becomesdifficult to expect a large damping force. If the degree of plasticityis greater than 420, the affinity of the silicone-based unvulcanizedrubber with contact surfaces of the pair of members is practically lost,and the pair of members slip with respect to the silicone-basedunvulcanized rubber in the relative movement of the pair of members withrespect to each other, thereby making it difficult to obtain asubstantial damping force based on the deformation of the silicone-basedunvulcanized rubber. In addition, even if the surfaces of the pair ofmembers in contact with such silicone-based unvulcanized rubber areformed as uneven surfaces for preventing the slippage, and thesilicone-based unvulcanized rubber is gripped, since the silicone-basedunvulcanized rubber having a degree of plasticity greater than 420 isextremely brittle, the silicone-based unvulcanized rubber is easilysheared (torn apart) in the relative movement of the pair of memberswith respect to each other, which also makes it difficult to obtain thedamping force based on the deformation of the silicone-basedunvulcanized rubber.

In addition, the silicone-based unvulcanized rubber is normally filledin the gap between the pair of members, if its degree of plasticity isgreater than 420, it becomes extremely difficult to fill thesilicone-based unvulcanized rubber between the pair of members without agap. If a gap is produced between each of the pair of members and thesilicone-based unvulcanized rubber after the filling of thesilicone-based unvulcanized rubber, there is a possibility that adesired damping force cannot be obtained.

From the above-described perspectives of the unnecessariness of theseal, the magnitude of the damping force obtained, affinity,brittleness, the ease of filling, durability, and the like, the degreeof plasticity of the silicone-based unvulcanized rubber is preferablynot less than 60 and not more than 320, more preferably not less than160 and not more than 320, as described above. If the degree ofplasticity is not less than 60, the fluidity of the silicone-basedunvulcanized rubber is practically lost, and the leakage of thesilicone-based unvulcanized rubber can be prevented by a simple sealingmechanism. If the degree of plasticity is not less than 160, the sealingmechanism can be practically omitted, and a relatively large dampingforce can be obtained. On the other hand, if the degree of plasticity ofthe silicone-based unvulcanized rubber is greater than 420, its affinitywith the contact surfaces of the pair of members becomes lost, asdescribed above, and the silicone-based unvulcanized rubber becomesbrittle and is easily sheared. However, in the case of thesilicone-based unvulcanized rubber having a degree of plasticity of notmore than 320, its affinity with the contact surfaces of the pair ofmembers improves, and the silicone-based unvulcanized rubber undergoesdeformation without much slipping with respect to the contact surfacesof the pair of members in the relative movement of the pair of memberswith respect to each other, thereby making it easy to obtain a targeteddamping force. Furthermore, the brittleness disappears, and thesilicone-based unvulcanized rubber desirably undergoes plasticdeformation in correspondence with the relative movement of the pair ofmembers with respect to each other; thus, even if the pair of membershaving the uneven surfaces formed thereon for gripping thesilicone-based unvulcanized rubber are used, it is possible to avoid asituation in which the silicone-based unvulcanized rubber is shearedinto pieces.

In the invention, as in the damper in accordance with a sixth aspect,the pair of members are disposed in such a manner as to be relativelyrotatable with respect to each other. Such a damper in accordance withthe sixth aspect is generally used for absorbing the rotational energyof a rotating member.

In the invention, as in the damper in accordance with a seventh aspect,at least one of the pair of members has an uneven surface in contactwith the silicone-based unvulcanized rubber. Here, the uneven surfacemay be adapted to prevent the slippage of the silicone-basedunvulcanized rubber in a vicinity of the uneven surface in the relativemovement of the pair of members. The uneven surface may be embodied bydiscretely disposed projections or grooves or by continuous projectionsor grooves, as will be described later, or may be embodied by a mattefinished or wrinkled uneven surface.

Such an uneven surface functions so as to grip the silicone-basedunvulcanized rubber in the vicinity of the uneven surface, with theresult that it is possible to prevent the slippage between each of thepair of members and the silicone-based unvulcanized rubber in therelative movement of the pair of members, and desired plasticdeformation is caused in the silicone-based unvulcanized rubber, therebyallowing the silicone-based unvulcanized rubber to absorb the targetedenergy. In cases where the surfaces of the silicone-based unvulcanizedrubber and the pair of members in contact therewith exhibit goodaffinity, and the slippage does not occur between each of the pair ofmembers and the silicone-based unvulcanized rubber, as described above,or that slippage is allowed, the surface of at least one of the pair ofmembers may be formed not as an uneven surface but as a smooth surface.

In the invention, as in the damper in accordance with an eighth aspect,at least one of the pair of members may have, on a surface thereof incontact with the silicon-based unvulcanized rubber, one of a projectionand a groove extending in a direction intersecting a direction of therelative movement.

Such a projection or a groove functions in the same way as the unevensurface of the damper in accordance with the seventh aspect and gripsthe silicone-based unvulcanized rubber in the vicinity of the projectionor the groove. Consequently, it is possible to prevent the slippagebetween each of the pair of members and the silicone-based unvulcanizedrubber in the relative movement of the pair of members, and thesilicone-based unvulcanized rubber is made to undergo desireddeformation to thereby absorb the targeted energy. In the same way asthe uneven surface, in cases where the surfaces of the silicone-basedunvulcanized rubber and the pair of members in contact therewith exhibitgood affinity, and the slippage does not occur between each of the pairof members and the silicone-based unvulcanized rubber, as describedabove, or that slippage is allowed, the surface of at least one of thepair of members may be formed as a smooth surface without having theabove-described projection or groove.

In the damper in accordance with the eighth aspect, the surface incontact with the silicone-based unvulcanized rubber may include acylindrical surface as in the damper in accordance with a ninth aspector may include one of an annular surface and a disk-like surface as inthe damper in accordance with a 10th aspect. In the case of the ninthaspect, one of the projection and the groove preferably extendssubstantially parallel to a center line of the cylindrical surface, andin the case of the 10th aspect, one of the projection and the groovepreferably extends in a radial direction of the one of the annularsurface and the disk-like surface.

In the invention, as in the damper in accordance with an 11th aspect,the pair of members may be disposed in such a manner as to be relativelylinearly movable with respect to each other. Such a damper in accordancewith the 11th aspect is generally used for absorbing the linearly movingenergy of a linearly moving member.

In the damper in accordance with the invention, one of the pair ofmembers is generally fixed, while the other member is disposed movablywith respect to the one member. However, such members may be members(parts) of a machine or an apparatus whose movement is to be damped, ormay alternatively be members added to such a machine or an apparatus. Inaddition, the silicone-based unvulcanized rubber in accordance with theinvention is sufficient if it is interposed between the pair of members,the silicone-based unvulcanized rubber is generally used by beingclosely filled in a space (gap) formed between the pair of members.

The damper in accordance with a 12th aspect of the invention is a damperfor an automobile seat which includes a housing serving as the onemember and having an arm portion and a housing body integral to the armportion, and a gap forming member serving as the other member andaccommodated rotatably in the housing body, the gap forming memberforming a gap in cooperation with an inner surface of the housing body,the silicone-based unvulcanized rubber being disposed in the gap, thedamper being adapted to transmit the rotation of the automobile seat tothe housing by means of the arm portion, and the gap forming memberbeing adapted to be fixed to a chassis on which the automobile seat isrotatably installed.

The damper in accordance with a 13th aspect of the invention is a damperfor an automobile seat which includes a housing serving as the onemember and having an arm portion and a housing body integral to the armportion, and a gap forming member serving as the other member andaccommodated rotatably in the housing body, the gap forming memberforming a gap in cooperation with an inner surface of the housing body,the silicone-based unvulcanized rubber being disposed in the gap, thehousing being adapted to be fixed by means of the arm portion to achassis on which the automobile seat is rotatably installed, and thedamper being adapted to transmit the rotation of the automobile seat tothe gap forming member.

The damper in accordance with a 14th aspect of the invention is a damperfor an automobile seat which includes a housing serving as the onemember and having a collar portion and a housing body integral to thecollar portion, and a gap forming member serving as the other member andaccommodated rotatably in the housing body, the gap forming memberforming a gap in cooperation with an inner surface of the housing body,the silicone-based unvulcanized rubber being disposed in the gap, thedamper being adapted to transmit the rotation of the automobile seat tothe housing by means of the collar portion, and the gap forming memberbeing adapted to be fixed to a chassis on which the automobile seat isrotatably installed.

The damper in accordance with a 15th aspect of the invention is a damperfor an automobile seat which includes a housing serving as the onemember and having a collar portion and a housing body integral to thecollar portion, and a gap forming member serving as the other member andaccommodated rotatably in the housing body, the gap forming memberforming a gap in cooperation with an inner surface of the housing body,the silicone-based unvulcanized rubber being disposed in the gap, thehousing being adapted to be fixed by means of the collar portion to achassis on which the automobile seat is rotatably installed, and thedamper being adapted to transmit the rotation of the automobile seat tothe gap forming member.

According to the above-described damper for an automobile seat, sincethe damping function is arranged to be obtained by the silicone-basedunvulcanized rubber, there is no risk of wear, a seal for preventingleakage can be omitted, and a large damping force can be easily obtainedeven if the damper is lightweight and compact.

In the invention, as in the damper for an automobile seat in accordancewith a 16th aspect, the housing body has a plurality of concentricarcuate projections, and the gap forming member has a plurality ofconcentric hollow cylindrical recessed portions in which the arcuateprojections of the housing body are respectively disposed with the gaptherebetween.

According to the damper for an automobile seat in accordance with the16th aspect, the area of the silicone-based unvulcanized rubber incontact with the housing body and the gap forming member in the gap canbe enlarged, so that it is possible to obtain an even greater energyabsorbing capability even if the damper is made compact.

In addition, in the invention, as in the damper for an automobile seatin accordance with a 17th aspect, a slit extending radially andcommunicating with the gap is preferably formed in the gap formingmember.

According to the damper for an automobile seat in accordance with the17th aspect, since the silicone-based unvulcanized rubber can be filledalso in the slit communicating with the gap, it is possible to preventthe slippage of the silicone-based unvulcanized rubber with respect tothe gap forming member by means of the slit. Moreover, when thesilicone-based unvulcanized rubber is filled into the gap, the fillingcan be effected through that slit, so that the silicone-basedunvulcanized rubber can be reliably and easily filled into the gap, andit is possible to avoid the occurrence of a gap portion in which thesilicone-based unvulcanized rubber is not filled between thesilicone-based unvulcanized rubber and each of the housing body and thegap forming member.

An automobile seat in accordance with the invention comprises the damperfor an automobile seat according to any one of the above-describedaspects, and a seat provided rotatably on the automobile chassis, therotation of the seat being transmitted to one of the housing and the gapforming member, and another one of the housing and the gap formingmember being fixed to the chassis.

According to the above-described automobile seat in accordance with theinvention, since the damping function is arranged to be obtained by thesilicone-based unvulcanized rubber, it is possible to obtain the effectsderived from the above-described damper, and it is possible to eliminatesuch as a shock occurring in the seat, e.g., a rear seat at the time ofits springing up or returning, sudden springing up of the seat due tosudden braking when the seat is unlocked, and sudden returning of thesprung-up seat due to sudden acceleration.

In the invention, as in the automobile seat in accordance with itssecond aspect, the seat is preferably provided with a backrestrotatably. It should be noted that the automobile seat in accordancewith the invention is not limited to such a seat on which a backrest isrotatably provided, and the seat is not limited to the rear seat, andmay be another seat inside the automobile.

According to the damper in accordance with the various aspects of theinvention described above, it is possible to provide a damper which hasno possibility of wear and makes it possible to eliminate a seal forpreventing leakage and to easily obtain a large damping force even ifthe damper is lightweight and compact.

According to the damper in accordance with the various aspects of theinvention described above, it is possible to provide a damper whichmakes it possible to obtain a large damping force and can be madecompact and which is particularly suitable for an automobile seat inwhich a backrest is arranged to be folded down and a seat is arranged tobe subsequently sprung up, as well as an automobile seat having thisdamper.

Hereafter, a description will be given of the present invention withreference to the preferred embodiments shown in the drawings. It shouldbe noted that the present invention is not limited to these embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A and 1B are explanatory diagrams of a preferred embodiment ofthe invention, in which FIG. 1A is a cross-sectional view taken in thedirection of arrows along line Ia-Ia shown in FIG. 1B, and FIG. 1B is across-sectional view taken in the direction of arrows along line Ib-Ibshown in FIG. 1A;

FIGS. 2A and 2B are explanatory diagrams of another preferred embodimentof the invention, in which FIG. 2A is a cross-sectional view taken inthe direction of arrows along line IIa-IIa shown in FIG. 2B, and FIG. 2Bis a cross-sectional view taken in the direction of arrows along lineIIb-IIb shown in FIG. 2A;

FIGS. 3A and 3B are explanatory diagrams of still another preferredembodiment of the invention, in which FIG. 3A is a cross-sectional viewtaken in the direction of arrows along line IIIa-IIIa shown in FIG. 3B,and FIG. 3B is a cross-sectional view taken in the direction of arrowsalong line IIIb-IIIb shown in FIG. 3A;

FIGS. 4A and 4B are enlarged explanatory diagrams of a portion of theembodiment shown in FIGS. 3A and 3B;

FIGS. 5A to 5D are explanatory diagrams of modifications of theembodiment shown in FIGS. 3A and 3B;

FIG. 6 is an explanatory diagram of a further preferred embodiment ofthe invention;

FIG. 7 is an explanatory diagram of a still further preferred embodimentof the invention;

FIG. 8 is a right-hand side elevational view of one half member of theembodiment shown in FIG. 7;

FIG. 9 is a left-hand side elevational view of a relatively rotatingmember of the embodiment shown in FIG. 7;

FIG. 10 is a left-hand side elevational view of the other half member ofthe embodiment shown in FIG. 7;

FIG. 11 is an explanatory diagram of a further preferred embodiment ofthe invention;

FIG. 12 is a right-hand side elevational view of a housing body of theembodiment shown in FIG. 11;

FIG. 13 is a left-hand side elevational view of a cover member of theembodiment shown in FIG. 11;

FIG. 14 is an explanatory diagram of a further preferred embodiment ofthe invention;

FIG. 15 is an explanatory diagram of a further preferred embodiment ofthe invention;

FIG. 16 is a left-hand side elevational view of a portion of theembodiment shown in FIG. 15;

FIG. 17 is a right-hand side elevational view of one disk-like member ofthe embodiment shown in FIG. 15;

FIG. 18 is a left-hand side elevational view of the other disk-likemember of the embodiment shown in FIG. 15;

FIG. 19 is an explanatory diagram of a further preferred embodiment ofthe invention;

FIG. 20 is an explanatory diagram of a right-hand side surface of onedisk-like member of the embodiment shown in FIG. 19;

FIG. 21 is an explanatory diagram of a left-hand side surface of theother disk-like member of the embodiment shown in FIG. 19;

FIG. 22 is a left-hand side elevational view of a portion of theembodiment shown in FIG. 19;

FIG. 23 is an explanatory diagram of a further preferred embodiment ofthe invention;

FIG. 24 is an explanatory diagram of a further preferred embodiment ofthe invention;

FIG. 25 is an explanatory diagram of a right-hand side surface of onedisk-like member of the embodiment shown in FIG. 24;

FIG. 26 is an explanatory diagram of a left-hand side surface of theother disk-like member of the embodiment shown in FIG. 24;

FIG. 27 is an explanatory diagram of a further preferred embodiment ofthe invention;

FIG. 28 is an explanatory diagram of a further preferred embodiment ofthe invention;

FIG. 29 is an explanatory diagram of an automobile seat in accordancewith a further preferred embodiment of the invention;

FIG. 30 is an explanatory cross-sectional view of the further embodimentshown in FIG. 29;

FIG. 31 is a view taken in the direction of arrows along line XXXI-XXXIshown in FIG. 30;

FIG. 32 is a cross-sectional view taken in the direction of arrows alongline XXXII-XXXII shown in FIG. 30;

FIG. 33 is a diagram explaining the operation of the embodiment shown inFIG. 29;

FIG. 34 is a diagram explaining the operation of the embodiment shown inFIG. 29;

FIG. 35 is an explanatory diagram of a further preferred embodiment ofthe invention;

FIG. 36 is a view taken in the direction of arrows along lineXXXVI-XXXVI shown in FIG. 35;

FIG. 37 is an explanatory diagram of a further preferred embodiment ofthe invention;

FIG. 38 is a partially enlarged explanatory diagram of the embodimentshown in FIG. 37;

FIG. 39 is a partially enlarged explanatory diagram of a furtherpreferred embodiment of the invention; and

FIG. 40 is an explanatory diagram of a further preferred embodiment ofthe invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

In FIGS. 1A and 1B, a damper 1 in this embodiment has silicone-basedunvulcanized rubber 4 interposed between a housing 2 and a shaft 3 whichserve as a pair of members arranged to be relatively movable withrespect to each other, or rotatable about an axis A in R directions inthis embodiment. The damper 1 is adapted to absorb relative rotationalenergy in the R directions between the housing 2 and the shaft 3 throughthe deformation of the silicone-based unvulcanized rubber 4.

The housing 2 has a hollow cylindrical member 5 with a bottom and acover member 6 secured to the hollow cylindrical member 5, and the shaft3 is disposed in such a manner as to be passed through a bottom portion7 of the hollow cylindrical member 5 and the cover member 6. Thesilicone-based unvulcanized rubber 4 having a degree of plasticity ofnot less than 30 and not more than 420, preferably not less than 60 andnot more than 320, more preferably not less than 160 and not more than320, is disposed in the housing 2 by being filled in an annular gapbetween an inner cylindrical surface 8 of the hollow cylindrical member5 and an outer cylindrical surface 9 of the shaft 3 in close contactwith the cylindrical surfaces 8 and 9.

In the damper 1 of this embodiment, seal rings 10 and 11 arerespectively fitted between the bottom portion 7 and the shaft 3, andbetween the cover member 6 and the shaft 3. In a case where thesilicone-based unvulcanized rubber 4 does not have much fluidity, theseal rings 10 and 11 may be omitted.

In a case where the damper 1 shown in FIGS. 1A and 1B is used for ahinge mechanism such as an openable cover of an apparatus, for example,the housing 2 is secured to such as a frame of the apparatus, while theshaft 3 is linked to a shaft of the hinge mechanism or is used as theshaft itself of the hinge mechanism.

In the damper 1 used for such an apparatus, deformation is caused in thesilicone-based unvulcanized rubber 4 by the rotation of the shaft 3 inthe R direction at the time of opening or closing of the cover or thelike, and the rotational energy of the cover is absorbed through thedeformation of the silicone-based unvulcanized rubber 4, thereby makingit possible to prevent a shock from occurring at the time of the openingor closing.

According to the damper 1, since the damping function is arranged to beobtained by the silicone-based unvulcanized rubber 4, there is nopossibility of wear, and a large damping force can be easily obtainedeven if the damper 1 is lightweight and compact. Moreover, by using thesilicone-based unvulcanized rubber 4 having such a large degree ofplasticity that the silicone-based unvulcanized rubber 4 does notsubstantially undergo natural fluidity, it is possible to omit the sealrings 10 and 11 for prevention of leakage.

With the damper 1 shown in FIGS. 1A and 1B, the hollow cylindricalmember 5 and the shaft 3 respectively have the cylindrical surfaces 8and 9 which are smooth, and the silicone-based unvulcanized rubber 4 isclosely filled in a cylindrical gap defined by the cylindrical surfaces8 and 9 in close contact with the cylindrical surfaces 8 and 9.Alternatively, however, at least one of the housing 2 and the shaft 3,or both of the housing 2 and the shaft 3 in this embodiment, may havecylindrical uneven surfaces 15 and 16 in contact with the silicone-basedunvulcanized rubber 4, as shown in FIGS. 2A and 2B. The uneven surface15 is formed as the cylindrical inner peripheral surface of the hollowcylindrical member 5 of the housing 2, while the uneven surface 16 isformed as the cylindrical outer peripheral surface of the shaft 3. Theuneven surfaces 15 and 16 grip the silicone-based unvulcanized rubber 4in the vicinities of the uneven surfaces 15 and 16 in the relativerotation of the housing 2 and the shaft 3 about the axis A in the Rdirections, thereby preventing the slippage of the silicone-basedunvulcanized rubber 4 with respect to the uneven surfaces 15 and 16.

The uneven surface 15 is formed on the surface, i.e., the aforementionedcylindrical surface 8, of the hollow cylindrical member 5 of the housing2 in contact with the silicone-based unvulcanized rubber 4 by aplurality of projections 17 extending in directions intersecting the Rdirection, i.e., in directions perpendicular thereto in this embodiment.Similarly, the uneven surface 16 is formed on the surface, i.e., theaforementioned cylindrical surface 9, of the shaft 3 in contact with thesilicone-based unvulcanized rubber 4 by a plurality of projections 18extending in directions intersecting the R direction, i.e., indirections perpendicular thereto in this embodiment.

With the damper 1 shown in FIGS. 2A and 2B and provided with the housing2 and the shaft 3 in which the projections 17 and 18 extending indirections perpendicular to the R direction are respectively provided onthe cylindrical surface 8 and the cylindrical surface 9 which aresurfaces in contact with the silicone-based unvulcanized rubber 4, it ispossible to prevent the slippage between, on the one hand, the housing 2and the shaft 3 and, on the other hand, the silicone-based unvulcanizedrubber 4 in the relative rotation of the housing 2 and the shaft 3 inthe R directions. Hence, the silicone-based unvulcanized rubber 4 isallowed to undergo desired plastic deformation, thereby making itpossible to cause the silicone-based unvulcanized rubber 4 toeffectively absorb the targeted energy.

In the damper 1 shown in FIGS. 2A and 2B, the seal rings 10 and 11similar to those of the damper 1 shown in FIGS. 1A and 1B are used forpreventing the leakage of the silicone-based unvulcanized rubber 4.Instead of these seal rings 10 and 11, labyrinths 21 and 22 may be usedto prevent the leakage of the silicone-based unvulcanized rubber 4, asshown in FIG. 3B. As shown in enlarged form in FIG. 4A, the labyrinth 21is formed by two annular projections 26 formed integrally on a steppedportion 25 between a large-diameter portion 23 and a small-diameterportion 24 of the shaft 3 as well as a plurality of annular grooves 27which are formed in the bottom portion 7 of the hollow cylindricalmember 5 and into which the projections 26 are inserted and fitted. Thelabyrinth 22 is formed in a similar manner.

In addition, instead of the labyrinths 21 and 22 shown in FIGS. 3B and4A, a labyrinth 28 such as the one shown in FIG. 4B may be used. Thelabyrinth 28 is formed by a plurality of annular grooves 30 provided inthe inner peripheral surface of a tubular portion 29 formed integrallyon the bottom portion 7 as well as a plurality of annular projections 31which are formed integrally on the outer peripheral surface of thesmall-diameter portion 24 of the shaft 3 and are fitted in the grooves30. It should be noted that, in the example shown in FIG. 4B, an annularrecess 35 extending along the direction of the axis A is formed in thesmall-diameter portion 24 of the shaft 3, and a projection 36 projectingin the radial direction is formed integrally on the outer peripheralsurface of the small-diameter portion 24 of the shaft 3. An annularportion 37 where the annular projection 31 is formed in thesmall-diameter portion 24 is snap-fitted to the tubular portion 29 withresiliency so as to be relatively slidable about the axis A in the Rdirections with respect to the tubular portion 29.

By using the labyrinths 21 and 22 or 28 such as those shown in FIGS. 4Aand 4B, it is possible to easily prevent the leakage of thesilicone-based unvulcanized rubber 4. In addition, by using the snap-fittype fitting as shown in FIG. 4B, it is possible to more easily preventthe leakage of the silicone-based unvulcanized rubber 4 over an extendedperiod.

Although the solid shaft 3 is used in the dampers 1 shown in FIGS. 1Aand 1B as well as 2A and 2B, a hollow shaft 3 may be alternatively used,as shown in FIGS. 3A and 3B. The arrangement provided is such that theshaft or the like with a hexagonal cross-sectional shape of a hingemechanism is fitted in a hollow portion 38 with a hexagonalcross-sectional shape of the shaft 3 so as not to idle by slipping aboutthe axis A in the R directions with respect to the shaft 3. As the shapeof the hollow portion for preventing such idling, instead of the hollowportion 38 with the hexagonal cross-sectional shape, it is possible touse an overlapping pair of hollow portions 41 each having a semicircularcross-sectional shape, a hollow portion 42 having a squarecross-sectional shape, a hollow portion 43 having a starlikecross-sectional shape, or a hollow portion 44 having a rectangularcross-sectional shape. The shaft or the like of the hinge mechanismhaving a cross-sectional shape complementary to each of these hollowportions 41 to 44 is adapted to be fitted in each of these hollowportions 41 to 44.

In addition, although the dampers 1 shown in FIGS. 1A and 1B as well as2A and 2B are examples in which the housing 2 and the shaft 3 which arerelatively long in the direction of the axis A are used as the pair ofmembers, the damper 1 may be constructed by using as the pair of membersa housing 51 jutting out in the radial direction and a relativelyrotating member 52 disposed inside the housing 51 in such a manner as tobe relatively rotatable about the axis A in the directions R, as shownin FIG. 6. In the damper 1 shown in FIG. 6, the housing 51 consists of apair of half members 54 and 55 secured to each other by means of rivets53 or the like, and each of the half members 54 and 55 has asmall-diameter inner peripheral-side hollow cylindrical portion 56, anannular plate portion 57 formed integrally on the hollow cylindricalportion 56, and a large-diameter outer peripheral-side hollowcylindrical portion 58 formed integrally on the annular plate portion57. The relatively rotating member 52 has a hollow shaft portion 61 andan annular plate portion 62 formed integrally on the shaft portion 61.In this embodiment, the silicone-based unvulcanized rubber 4 isinterposed in an annular gap between the housing 51 and the relativelyrotating member 52.

In the damper 1 shown in FIG. 6 as well, deformation is caused in thesilicone-based unvulcanized rubber 4 by the relative rotation of therelatively rotating member 52 in the R directions with respect to thehousing 51 during the opening or closing of the cover or the like of theapparatus, and the rotational energy of the cover or the like isabsorbed by the deformation of the silicone-based unvulcanized rubber 4,thereby making it possible to prevent a shock from occurring at the timeof the opening or closing. Since the damping function is thus obtainedby the silicone-based unvulcanized rubber 4, there is no possibility ofwear, and a large damping force can be easily obtained even if thedamper 1 is lightweight and compact.

In the damper 1 shown in FIG. 6, an inner annular surface 65 of theannular plate portion 57 and an inner cylindrical surface 66 of thehollow cylindrical portion 58, as well as obverse and reverse annularsurfaces 67 and 68 of the annular plate portion 62 and an outerperipheral cylindrical surface 69 of the annular plate portion 62, whichare in contact with the silicone-based unvulcanized rubber 4, are formedas smooth surfaces. Alternatively, however, as shown in FIGS. 7 to 10,these surfaces 65, 66, 67, 68, and 69 may be formed as uneven surfacesby integrally forming thereon projections extending in directionsintersecting the direction of relative rotation of the relativelyrotating member 52 about the axis A in the R directions with respect tothe housing 51, i.e., in directions perpendicular to the direction ofrelative rotation in this embodiment, thereby preventing the slippage ofthe silicone-based unvulcanized rubber 4 with respect to the housing 51and the relatively rotating member 52 in that relative rotation in the Rdirections.

Namely, in the damper 1 shown in FIGS. 7 to 10, on the annular surfaces65 of the annular plate portions 57 and on the obverse and reverseannular surfaces 67 and 68 of the annular plate portion 62 respectivelyopposing the annular surfaces 65, a plurality of projections 71, 72, 73,and 74 extending in the radial directions of those annular surfaces 65,67, and 68 are integrally formed. The respective annular surfaces 65,67, and 68 are thus formed as uneven surfaces in contact with thesilicone-based unvulcanized rubber 4. Similarly, a plurality ofprojections 75 and 76 extending substantially parallel to a center lineA of the cylindrical surfaces 66 and 69 are integrally formed on thecylindrical surface 66 of the hollow cylindrical portion 58 of each halfmember 54 as well as the outer peripheral cylindrical surface 69 of theannular plate portion 62 opposing the cylindrical surface 66. Thus therespective cylindrical surfaces 66 and 69 are formed as uneven surfacesin contact with the silicone-based unvulcanized rubber 4.

In the damper 1 shown in FIGS. 7 to 10 as well, in the same way as thedamper 1 shown in FIG. 6, deformation is caused in the silicone-basedunvulcanized rubber 4 by the relative rotation of the relativelyrotating member 52 about the axis A in the R directions with respect tothe housing 51, and this rotational energy can be absorbed by thedeformation of the silicone-based unvulcanized rubber 4. Moreover, sincethe respective projections 71 to 76 firmly grip the silicone-basedunvulcanized rubber 4 in the vicinities of the projections 71 to 76 inthat relative rotation, it is possible to prevent a situation in whichthe silicone-based unvulcanized rubber 4 slips with respect to therelatively rotating member 52 and the housing 51, thereby making itpossible to reliably cause plastic deformation in the silicone-basedunvulcanized rubber 4.

It should be noted that, in the damper 1 shown in FIGS. 7 to 10, thehollow cylindrical portion 58 of the half member 54 consists of a hollowcylindrical portion 81 with a large thickness and a hollow cylindricalportion 82 with a small thickness formed integrally on the hollowcylindrical portion 81. The hollow cylindrical portion 82 has its outerperipheral surface abutting against the cylindrical surface 66 of thehollow cylindrical portion 58 of the half member 55, and is interiorlyfitted to the hollow cylindrical 58 of that half member 55. In addition,the above-mentioned labyrinths 21 and 22 are provided instead of theseal rings 10 and 11.

Further, in the present invention, the damper 1 may be constructed asshown in FIGS. 11 to 13. The damper 1 shown in FIGS. 11 to 13 has thesilicone-based unvulcanized rubber 4 interposed between a housing body85 and a cover member 86 which serve as the pair of members disposed insuch a manner as to be relatively rotatable about the axis A in the Rdirections with respect to each other.

The housing body 85 includes a hollow cylindrical shaft portion 87, anannular plate portion 88 formed integrally on the shaft portion 87, anda hollow cylindrical portion 89 formed integrally on the annular plateportion 88. The shaft portion 87 has a large-diameter shaft portion 90and a small-diameter shaft portion 91 formed integrally on thelarge-diameter shaft portion 90. The annular plate portion 88 has athick plate portion 92 and a thin plate portion 93 which is formedintegrally on the thick plate portion 92 and on which the hollowcylindrical portion 89 is integrally formed. An inner peripheral surface94 of the hollow cylindrical portion 89 is formed as an uneven surfacefor fitting and for a labyrinth.

The cover member 86 includes a hollow cylindrical portion 95, a collarportion 96 formed integrally on the hollow cylindrical portion 95, anannular plate portion 97 formed integrally on the hollow cylindricalportion 95, and a hollow cylindrical portion 98 formed integrally on theannular plate portion 97. An outer peripheral surface 99 of the hollowcylindrical portion 98 is formed as an uneven surface which iscomplementary to the uneven surface of the inner peripheral surface 94of the hollow cylindrical portion 89. The aforementioned labyrinth 21 isformed in the collar portion 96 and a stepped portion 101 between thelarge-diameter shaft portion 90 and the small-diameter shaft portion 91.The housing body 85 and the cover member 86 are fitted to each other atthe inner peripheral surface 94 of the hollow cylindrical portion 89 andthe outer peripheral surface 99 of the hollow cylindrical portion 98 insuch a manner as to be relatively rotatable about the axis A in the Rdirections with respect to each other. The silicone-based unvulcanizedrubber 4 is disposed by being filled in a gap between, on the one hand,an inner annular surface 105 and an outer peripheral-side cylindricalsurface 106 of the thick plate portion 92 and, on the other hand, aninner annular surface 107 of the annular plate portion 97 and an innercylindrical surface 108 of the hollow cylindrical 98.

In the damper 1 shown in FIGS. 11 to 13 as well, on the annular surfaces105 and the cylindrical surface 106 of the thick plate portion 92 and onthe annular surface 107 of the annular plate portion 97 and thecylindrical surface 108 of the hollow cylindrical portion 98respectively opposing the annular surface 105 and the cylindricalsurface 106, a plurality of projections 111 and 112 extending in theradial directions of those annular surfaces 105 and 107, as well as aplurality of projections 113 and 114 extending substantially parallel tothe center line A of the cylindrical surfaces 106 and 108, arerespectively formed integrally. The respective annular surfaces 105 and107 and cylindrical surfaces 106 and 108 are thus formed as unevensurfaces in contact with the silicone-based unvulcanized rubber 4.

In the damper 1 shown in FIGS. 11 to 13, the housing body 85 and thecover member 86 are fitted to each other at the inner peripheral surface94 of the hollow cylindrical portion 89 and the outer peripheral surface99 of the hollow cylindrical portion 98. Alternatively, however, anarrangement may be provided as shown in FIG. 14. Namely, an annulargroove 115 extending along the direction of the axis A is formed in thelarge-diameter shaft portion 90, and an annular collar portion 116 isformed integrally thereon. Further, an annular collar portion 117 isformed integrally on the hollow cylindrical portion 89, and the innerperipheral surface 94 of the hollow cylindrical portion 89 is formed tobe smooth. Meanwhile, an annular groove 118 extending along thedirection of the axis A is formed in the hollow cylindrical portion 95,and an annular inner peripheral surface 119 of the collar portion 96 isformed as an uneven surface, while an annular groove 120 extending alongthe direction of the axis A is formed in the hollow cylindrical portion98. Thus, the cover member 86 is fitted to the housing body 85 in asnap-fitting manner by means of the collar portions 116 and 117 in sucha manner as to be relatively rotatable about the axis A in the Rdirections with respect to each other.

In the dampers 1 shown in FIGS. 11 to 13 and FIG. 14 as well,deformation is caused in the silicone-based unvulcanized rubber 4 by therelative rotation of the housing body 85 in the R directions withrespect to the cover member 86, and this rotational energy can beabsorbed by the deformation of the silicone-based unvulcanized rubber 4.Moreover, since the respective projections 111 to 114 firmly grip thesilicone-based unvulcanized rubber 4 in the vicinities of theprojections 111 to 114 in that relative rotation, it is possible toprevent a situation in which the silicone-based unvulcanized rubber 4slips with respect to the housing body 85 and the cover member 86,thereby making it possible to reliably cause plastic deformation in thesilicone-based unvulcanized rubber 4.

Further, instead of the above-described construction, the damper 1 maybe constructed as shown in FIGS. 15 to 18. The damper 1 shown in FIGS.15 to 18 has the silicone-based unvulcanized rubber 4 interposed betweena pair of disk-like members 121 and 122 which serve as the pair ofmembers disposed in such a manner as to be relatively rotatable aboutthe axis A in the R directions with respect to each other.

The disk-like member 121 includes a disk-like portion 123, a hollowcylindrical portion 124 formed integrally on an outer edge of thecylindrical portion 123, and an annular collar portion 125 formedintegrally on one end face of the hollow cylindrical portion 124. Thedisk-like portion 123 includes a thick disk-like portion 127 having adouble stepped portion 126 at its outer edge and a thin annular portion128 which is formed integrally on the outer edge of the disk-likeportion 127 and on which the hollow cylindrical portion 124 isintegrally formed.

The disk-like member 122 includes a disk-like portion 131 and a hollowcylindrical portion 132 formed integrally on an outer edge of thecylindrical portion 131. An annular groove 133 extending parallel to theaxis A is formed in the hollow cylindrical portion 132, and a pluralityof annular projections 134 for fitting in annular grooves formed in aninner peripheral surface of the hollow cylindrical portion 124 areformed integrally on an outer peripheral surface of the hollowcylindrical portion 132. Thus, the disk-like member 122 is fitted to thedisk-like member 121 in a snap-fitting manner by means of the collarportion 125 in such a manner as to be relatively rotatable about theaxis A in the R directions.

In addition, in the damper 1 shown in FIGS. 15 to 18, on an innerdisk-like surface 141 of the disk-like portion 123 and a cylindricalsurface 142 defining the stepped portion 126 and on an inner disk-likesurface 143 of the disk-like portion 131 and an inner cylindricalsurface 144 of the cylindrical portion 132 respectively opposing thedisk-like surface 141 and the cylindrical surface 142, a plurality ofprojections 145 and 146 extending in the radial directions from thecenter A of those disk-like surfaces 141 and 143, as well as a pluralityof projections 147 and 148 extending substantially parallel to thecenter line A of the cylindrical surfaces 142 and 144, are respectivelyformed integrally. The respective disk-like surfaces 141 and 143 andcylindrical surfaces 142 and 144 are thus formed as uneven surfaces incontact with the silicone-based unvulcanized rubber 4.

The damper 1 shown in FIGS. 15 to 18 further includes mounting members152 and 153 which are respectively secured to the disk-like members 121and 122 by means of screws 151. The disk-like member 121 is fixed to,for example, a frame member or the like of an apparatus by means of themounting member 152, while the disk-like member 122 is connected bymeans of the mounting member 152 to a member such as a shaft fordampening the rotation of such as the apparatus.

In the damper 1 shown in FIGS. 15 to 18 as well, deformation is causedin the silicone-based unvulcanized rubber 4, which is filled in the gapbetween the disk-like portion 123 and the disk-like portion 131, by therelative rotation of the disk-like member 121 about the axis A in the Rdirections with respect to the disk-like member 122, and this rotationalenergy can be absorbed by the deformation of the silicone-basedunvulcanized rubber 4. Moreover, since the respective projections 145 to148 firmly grip the silicone-based unvulcanized rubber 4 in thevicinities of the projections 145 to 148 in that relative rotation, itis possible to prevent a situation in which the silicone-basedunvulcanized rubber 4 slips with respect to the disk-like members 121and 122, thereby making it possible to reliably cause plasticdeformation in the silicone-based unvulcanized rubber 4.

Although, in the damper 1 shown in FIGS. 15 to 18, the gap where thesilicone-based unvulcanized rubber 4 is filled extends straightly in theradial directions, the damper 1 may be alternatively constructed suchthat the gap where the silicone-based unvulcanized rubber 4 is filledextends in a zigzag manner in the radial directions, as shown in FIGS.19 to 22.

Namely, in the damper 1 shown in FIGS. 19 to 22, the disk-like member121 integrally has on the disk-like surface 141 of the disk-like portion123 a central circular projection 161 and a plurality of annularprojections 162 arranged concentrically with the central circularprojection 161 as the center. Meanwhile, the disk-like member 122 has onthe disk-like surface 143 of the disk-like portion 131 a centralcircular groove 163 in which the central circular projection 161 isdisposed with a gap therebetween, as well as a plurality of annulargrooves 164 in which the respective annular projections 162 are disposedwith the gap therebetween and which are arranged concentrically with thecentral circular groove 163 as the center. A zigzag gap is formed in theradial direction between the disk-like member 121 and the disk-likemember 122 by the central circular projection 161 and the annularprojections 162 as well as by the central circular groove 163 and theannular grooves 164, and the silicone-based unvulcanized rubber 4 isfilled in such a gap.

In the damper 1 shown in FIGS. 19 to 22 as well, deformation is causedin the silicone-based unvulcanized rubber 4, which is filled in the gapbetween the disk-like portion 123 and the disk-like portion 131, by therelative rotation of the disk-like member 121 about the axis A in the Rdirections with respect to the disk-like member 122, and this rotationalenergy can be absorbed by the deformation of the silicone-basedunvulcanized rubber 4. Moreover, since the zigzag gap is formed betweenthe disk-like member 121 and the disk-like member 122, the area ofcontact between, on the one hand, the silicone-based unvulcanized rubber4 and, on the other hand, the disk-like portion 123 and the disk-likeportion 131 increases, so that a large damping force can be obtainedeven if the damper 1 is made compact.

In the damper 1 shown in FIGS. 19 to 22, mounting portions 165 and 166corresponding to the mounting members 152 and 153 are respectivelyformed integrally on the disk-like portion 123 and the disk-like portion131, and the disk-like member 121 and the disk-like member 122 arefitted to each other at an inner uneven cylindrical surface 167 of thehollow cylindrical portion 124 and an outer uneven cylindrical surface168 of the hollow cylindrical portion 132 in such a manner as to berelatively rotatable about the axis A in the R directions with respectto each other.

In the damper 1 shown in FIGS. 19 to 22, a labyrinth 169 similar to thelabyrinths 21 and 22 may be provided on outer sides of the outermostperipheral annular projection 162 and the outermost peripheral annulargroove 164, as shown in FIG. 23, so as to prevent the leakage of thesilicone-based unvulcanized rubber 4.

In the dampers 1 shown in FIGS. 19 to 22 and FIG. 23, the disk-likesurface 141 including the cylindrical side surface of the centralcircular projection 161 and the cylindrical inner and outer peripheralsurfaces and top surfaces of the annular projections 162, as well as thedisk-like surface 143 including the cylindrical side surface of thecentral circular groove 163 and the cylindrical inner and outerperipheral surfaces and bottom surfaces of the annular grooves 164, arerespectively formed as smooth surfaces. Alternatively, however, as shownin FIGS. 24 to 26, a plurality of projections 171 and 172 which extendsubstantially parallel to the center line A on the cylindrical sidesurface of the central circular projection 161, the cylindrical innerand outer peripheral surfaces of the annular projections 162, thecylindrical side surface of the central circular groove 163, and thecylindrical inner and outer peripheral surfaces of the annular grooves164, and which on the other surfaces extend in the radial directions ofthe disk-like surfaces 141 and 143, i.e., extend radially andrespectively continue, may be integrally formed on these surfaces.

In the damper 1 shown in FIGS. 24 to 26 as well, deformation is causedin the silicone-based unvulcanized rubber 4, which is filled in the gapbetween the disk-like portion 123 and the disk-like portion 131, by therelative rotation of the disk-like member 121 about the axis A in the Rdirections with respect to the disk-like member 122, and this rotationalenergy can be absorbed by the deformation of the silicone-basedunvulcanized rubber 4. Moreover, since the respective projections 171and 172 firmly grip the silicone-based unvulcanized rubber 4 in thevicinities of the projections 171 and 172 in that relative rotation, itis possible to prevent a situation in which the silicone-basedunvulcanized rubber 4 slips with respect to the disk-like members 121and 122, thereby making it possible to reliably cause plasticdeformation in the silicone-based unvulcanized rubber 4. Furthermore,since the zigzag gap is formed between the disk-like member 121 and thedisk-like member 122, the area of contact between, on the one hand, thesilicone-based unvulcanized rubber 4 and, on the other hand, thedisk-like portion 123 and the disk-like portion 131 increases, so that alarge damping force can be obtained even if the damper 1 is madecompact.

Although the respective dampers 1 in the above-described embodiments arecapable of absorbing the rotational energy and damping the rotation asdesired, the present invention is also applicable to an arrangementwhich linearly moves, as shown in FIGS. 27 and 28, and its linearlymoving energy can be satisfactorily absorbed, thereby making it possibleto damp the linear motion as desired.

The damper 1 shown in FIG. 27 has the silicone-based unvulcanized rubber4 interposed between a cylinder 201 and a cylindrical rod 202 whichserve as the pair of members disposed in such a manner as to berelatively movable, or linearly movable in directions B in thisembodiment, with respect to each other. This damper 1 is adapted toabsorb the relative linearly moving energy in the B directions betweenthe cylinder 201 and the cylindrical rod 202 through the deformation ofthe silicone-based unvulcanized rubber 4.

The cylinder 201 has a hollow cylindrical portion 203 with a bottom anda cover portion 204 secured to one end face of the cylindrical portion203. The rod 202 is passed through a bottom portion 205 of the hollowcylindrical portion 203 and the cover portion 204 in such a manner as tobe linearly movable in the B direction, and projects outside thecylinder 201. The rod 202 has an enlarged portion 206 inside thecylinder 201, and the seal rings 10 and 11 are respectively fittedbetween the bottom portion 205 and the rod 202 and between the coverportion 204 and the rod 202.

In the damper 1 which is shown in FIG. 27 and in which thesilicone-based unvulcanized rubber 4 is closely filled in a space (gap)between the cylinder 201 and the rod 202, deformation (plasticdeformation) is caused in the silicone-based unvulcanized rubber 4 bythe enlarged portion 206 in the relative linear motion of the rod 202 inthe B directions with respect to the cylinder 201, and the linearlymoving energy in the B directions is absorbed by this deformation of thesilicone-based unvulcanized rubber 4.

Although, in the damper 1 shown in FIG. 27, the silicone-basedunvulcanized rubber 4 is deformed by causing the silicone-basedunvulcanized rubber 4 to undergo plastic flow by the enlarged portion206, the silicone-based unvulcanized rubber 4 may be alternativelydeformed by causing the silicone-based unvulcanized rubber 4 to undergoplastic flow by a recessed portion 211 provided in a hollow cylindricalmember 210, as shown in FIG. 28.

The damper 1 shown in FIG. 28 has the silicone-based unvulcanized rubber4 interposed between the hollow cylinder 210 and a linearly movingmember 212 which serve as the pair of members disposed in such a manneras to be relatively linearly movable in the directions B with respect toeach other. This damper 1 is adapted to absorb the relative linearlymoving energy in the B directions between the hollow cylindrical member210 and the linearly moving member 212 through the deformation of thesilicone-based unvulcanized rubber 4.

The hollow cylindrical member 210 has the recessed portion 211 in itsinner cylindrical surface, while the linearly moving member 212 has acylindrical rod 213 and a pair of disk-like collars 214 and 215 whichare secured to the rod 213 and are in contact with the inner cylindricalsurface of the hollow cylindrical member 210 at their annular outeredges in such a manner as to be slidable in the B directions. The sealrings 10 and 11 are respectively fitted between the collar 214 and thehollow cylindrical member 210 and between the collar 215 and the hollowcylindrical member 210.

Also in the damper 1 which is shown in FIG. 28 and in which thesilicone-based unvulcanized rubber 4 is closely filled in the space(gap) between the hollow cylindrical member 210 and the linearly movingmember 212, deformation (plastic deformation) is caused in thesilicone-based unvulcanized rubber 4 by the recessed portion 211 in therelative linear motion of the linearly moving member 212 in the Bdirections with respect to the hollow cylindrical member 210, and thelinearly moving energy in the B directions is absorbed by thisdeformation of the silicone-based unvulcanized rubber 4.

It should be noted that the damper 1 may be constructed by providing,instead of the recessed portion 211, the enlarged portion 206 such asthe one shown in FIG. 27 on the inner cylindrical surface of the hollowcylindrical member 210 shown in FIG. 28, or the damper 1 may beconstructed by providing, instead of the enlarged portion 206, therecessed portion 211 such as the one shown in FIG. 28 on the surface ofthe rod 202 shown in FIG. 27.

Next, an example of a damper suitable for use in an automobile seat andan example of an automobile seat using such a damper are shown in FIGS.29 to 32. In FIGS. 29 to 32, the damper 1 for an automobile seat in thisembodiment has a housing 304 serving as one member and a gap formingmember 307 and a cover member 309 serving as other members. The housing304 integrally has an arm portion 302 and a housing body 303. The gapforming member 307 is accommodated in the housing body 303 in such amanner as to be rotatable in R1 and R2 directions, and forms a gap 306in cooperation with an inner surface 305 of the housing body 303. Thesilicone-based unvulcanized rubber 4 is disposed in the gap 306, and thecover member 309 is secured to the gap forming member 307.

A through hole 311 for connection is formed in the arm portion 302, andthe housing body 303 integrally has a hollow cylindrical member 312, aclosure portion 314 which closes one end face of the hollow cylindricalmember 312 and in an inner surface of which a central recessed portion313 is formed, and a plurality of concentric arcuate projections 315provided on an inner surface of the closure portion 314 with the centralrecessed portion 313 as the center.

The gap forming member 307 has a central projection 321 fitted in thecentral recessed portion 313 in such a manner as to be rotatable in theR1 and R2 directions, a plurality of concentric hollow cylindricalprojections 322 on the inner sides of which the arcuate projections 315of the housing body 303 are disposed with the gap 306 therebetween andwhich are provided with the central projection 321 as the center, acentral recessed portion 323 formed in the central projection 321, and ahole 324 communicating with the central recessed portion 323. In thehole 324, serrations extending along the axial direction are formed onthe gap forming member 307. A plurality of slits 325 which extend in theradial directions, communicate with the gap 306, and are arranged atequiangular intervals in the circumferential direction in thisembodiment are formed in the gap forming member 307.

The silicone-based unvulcanized rubber 4 is disposed in the housing body303 by being filled in the gap 306 in close contact with the housingbody 303 and the gap forming member 307.

The cover member 309 is secured to the gap forming member 307 by screws326, and seal members (O-rings) 327 and 328 are respectively fittedbetween the cover member 309 and the gap forming member 307 and betweenthe cover member 309 and the hollow cylindrical member 312. In a casewhere the silicone-based unvulcanized rubber 4 does not have muchfluidity, the seal members 327 and 328 may be omitted. It should benoted that the prevention of the cover member 309 from coming off thehollow cylindrical member 312 is effected by a ring 329 such as anE-ring fitted to the hollow cylindrical member 312.

To use the damper 1 of this embodiment shown in FIGS. 29 to 32, the armportion 302 is connected, by means of a screw or a pin 333 inserted inthe through hole 311, to a seat frame 332 which rotates with therotation in the R1 and R2 directions of a rear seat 331 serving as, forexample, an automobile seat, and a serrated tip portion 335 and a mostdistal end portion 336 of a fixed shaft 334 of a hinge mechanism (notshown) of the rear sheet 331 are respectively fitted in the hole 324 andthe central recessed portion 323.

Accordingly, in this embodiment, the rotation of the rear seat 331 inthe R1 and R2 directions is adapted to be transmitted to the housing 304by means of the arm portion 302, and the gap forming member 307 isadapted to be fixed to a chassis 337 on which the rear seat 331 isrotatably installed. A backrest 338 connected rotatably to the rear seat331 is rotatable in C and D directions with respect to the rear seat 331by means of a hinge mechanism 339.

The rotation of the seat frame 332 in the R1 direction is normallyprohibited by a known lock mechanism 340, and the seat frame 332 isadapted to be rotatable in the R1 direction, as shown in FIG. 34, by theunlocking of the lock mechanism 340. Accordingly, after the backrest 338is rotated in the C direction, as shown in FIG. 33, if the rear seat 331is rotated in the R1 direction, as shown in FIG. 34, it is possible tosecure a large accommodation space within the vehicle compartment.

In the automobile seat of this example, which includes theabove-described damper 1 and the seat, i.e., the rear seat 331 in thisembodiment, provided rotatably in the R1 and R2 directions with respectto the chassis 337 of the automobile, and in which the rotation of therear seat 331 in the R1 and R2 directions is adapted to be transmittedto one of the housing 304 and the gap forming member 307, i.e., thehousing 304 in this embodiment, and the other one of the housing 304 andthe gap forming member 307, i.e., the gap forming member 307 in thisembodiment, is fixed to the chassis 337, deformation can be caused inthe silicone-based unvulcanized rubber 4 by the rotation of the housingbody 303 in the R1 and R2 directions with respect to the gap formingmember 307 via the arm portion 302 in the rotation of the rear seat 331in the R1 and R2 directions, so as to absorb the rotational energy ofthe rear seat 331 by the deformation of the silicone-based unvulcanizedrubber 4, thereby making it possible to prevent the occurrence of ashock at the time of the rotation. In addition, it is possible to dampthe returning of the rear seat 331 in the R2 direction due to the quickstart of the automobile with the rear seat 331 sprung up as shown inFIG. 34, and it is possible to damp the springing up of the rear seat331 in the R1 direction due to sudden braking when the lock mechanism340 is unlocked.

In addition, according to the damper 1 shown in FIGS. 29 to 32, sincethe damping function is obtained by the silicone-based unvulcanizedrubber 4, there is no possibility of wear, seals for preventing leakagecan be omitted, and a large damping force can be easily obtained even ifthe damper 1 is lightweight and compact. Furthermore, since there areprovided the projections 315 and the projections 322 on the inner sidesof which the projections 315 are disposed with the gap 306 therebetween,the area of the silicone-based unvulcanized rubber 4 contacting thehousing body 303 and the gap forming member 307 can be enlarged at thegap 306, and it is possible to obtain a large energy absorbingcapability even if the damper 1 is made compact. In addition, since theslits 325 are formed in the gap forming member 307, it is possible toprevent the slippage of the silicone-based unvulcanized rubber 4 withrespect to the gap forming member 307 by virtue of the slits 325.Moreover, when the silicone-based unvulcanized rubber 4 is filled intothe gap 306, the filling can be effected through these slits 325, sothat the silicone-based unvulcanized rubber 4 can be reliably and easilyfilled into the gap 306, and it is possible to avoid the occurrence of agap portion in which the silicone-based unvulcanized rubber 4 is notfilled between, on the one hand, the silicone-based unvulcanized rubber4 and, on the other hand, the housing body 303 and the gap formingmember 307.

With the damper 1 shown in FIGS. 29 to 32 referred to above, thearrangement provided is such that the gap forming member 307 is fixed,while the housing 304 is rotated with the rotation of the rear seat 331.Alternately, however, an arrangement may be provided such that the armportion 302 is secured by means of a screw, a pin, or the like to abracket 354 installed and secured to the chassis 337, the fixed shaft334 of the hinge mechanism (not shown) of the rear seat 331 is used as arotating shaft which is rotated in the same direction as that of therear seat 331 as the rear seat 331 is rotated in the R1 or R2 direction,and the serrated tip portion 335 and the most distal end portion 336 ofthis rotating shaft are respectively fitted in the hole 324 and thecentral recessed portion 323 of the gap forming member 307. The housing304 is thereby fixed by means of the arm portion 302 to the chassis 337on which the rear seat 331 is rotatably installed, so as to transmit therotation of the rear seat 331 to the gap forming member 307.

Furthermore, although in the above-described embodiment the damper 1 isconstructed by including the housing 304 which integrally has the armportion 302 and the housing body 303, the damper 1 may be alternativelyconstructed by including the housing 304 which integrally has an annularcollar portion 351 and the housing body 303, as shown in FIGS. 35 and36. In this case, the collar portion 351 having a plurality of throughholes 352 into which screws, pins, or the like for fixing are insertedis provided integrally on the hollow cylindrical member 312 of thehousing body 303.

In the damper 1 shown in FIGS. 35 and 36 as well, an arrangement may beprovided such that the collar portion 351 is secured by means of screws,pins, or the like to one end of a connecting member (not shown) havingthe other end secured to the seat frame 332, and the rotation of therear seat 331 in the R1 and R2 directions is thereby transmitted to thehousing 304 by means of the collar portion 351, while the gap formingmember 307 is fixed to the chassis 337 on which the rear seat 331 isinstalled so as to be rotatable in the R1 and R2 directions.Alternately, an arrangement may be provided such that the collar portion351 is secured by means of screws, pins, or the like to the bracket 354installed and secured to the chassis 337, the fixed shaft 334 of thehinge mechanism (not shown) of the rear seat 331 is used as the rotatingshaft which is rotated in the same direction as that of the rear seat331 as the rear seat 331 is rotated in the R1 or R2 direction, and theserrated tip portion 335 and the most distal end portion 336 of thisrotating shaft are respectively fitted in the hole 324 and the centralrecessed portion 323 of the gap forming member 307. The housing 304 isthereby fixed by means of the collar portion 351 to the chassis 337 onwhich the rear seat 331 is installed in such a manner as to be rotatablein the R1 and R2 directions, so as to transmit the rotation of the rearseat 331 in the R1 and R2 directions to the gap forming member 307.

Although in the above-described embodiment the cover member 309 issecured to the gap forming member 307 by means of the screws 326, anarrangement may be alternatively provided such that, as shown in FIG.37, by using the cover member 309 having an externally threaded portion362 on its outer peripheral surface 361 and the housing 304 having aninternally threaded portion 363 on the inner surface 305 of the housingbody 303, the cover member 309 is secured to the housing body 303 bythreadedly engaging the externally threaded portion 362 with theinternally threaded portion 363, and the cover member 309 is fixed to orrotated together with the housing body 303. In this case, if a gap 364communicating with the gap 306 is also provided between the cover member309 and the gap forming member 307, and the silicone-based unvulcanizedrubber 4 is filled also in the gap 364, it is possible to obtain an evengreater energy absorbing capability. In addition, as in the case of thedamper 1 shown in FIG. 37, the central recessed portion 323 of the gapforming member 307 and the most distal portion 336 of the fixed shaft334 may be omitted. Further, the seal members 327 and 328 may beomitted, and a labyrinth mechanism 371 may be provided between the covermember 309 and the gap forming member 307 instead of the seal members327 and 328.

The labyrinth mechanism 371 illustrated in detail in FIG. 38 has aplurality of concentric hollow cylindrical projections 372 formedintegrally on the gap forming member 307 and a plurality of concentricrecessed portions 373 which are provided in the cover member 309 andinto which the respective projections 372 are inserted, and a labyrinth374 is formed by the projections 372 and the recessed portions 373. Theleakage of the silicone-based unvulcanized rubber 4 to the outside fromthe gap between the cover member 309 and the gap forming member 307 maybe prevented by such a labyrinth 374.

In addition, the labyrinth mechanism 371 may be constructed such that,as shown in FIG. 39, an annular inclined surface 375 is provided on oneof the projections 372, and this inclined surface 375 is caused to abutagainst the cover member 309, in order to form the labyrinth mechanism371 by separated labyrinths 376 and 377. According to the labyrinthmechanism 371 shown in FIG. 39, it is possible to prevent the leakage ofthe silicone-based unvulcanized rubber 4 more reliably.

Although in the above-described embodiments the cover member 309 whichis separate from the gap forming member 307 is provided, the damper 1may be constructed by omitting the cover member 309, as shown in FIG.40. In this case as well, the prevention of the gap forming member 307from coming off the hollow cylindrical member 312 may be effected by thering 329 such as an E-ring fitted to the aforementioned hollowcylindrical member 312. Alternately, by using the gap forming member 307having the externally threaded portion 382 on its outer peripheralsurface 381, the externally threaded portion 382 may be threadedlyengaged with the internally threaded portion 363 of the housing body303, and the gap forming member 307 may be fitted in the housing body303 in such a manner as to be rotatable in the R1 and R2 directions. Inthis case, to ensure that the gap forming member 307 becomes relativelymovable in the axial direction, i.e., in E directions, with respect tothe housing body 303 and the fixed shaft (or the rotating shaft) 334 inthe relative rotation of the gap forming member 307 in the R1 and R2directions with respect to the housing body 303, a gap 383 whichcommunicates with the gap 306 and in which the silicone-basedunvulcanized rubber 4 is similarly filled is provided between the gapforming member 307 and the housing body 303 with respect to the Edirections as well. Meanwhile, a gap 384 in the E directions is providedbetween the tip portion 335 of the fixed shaft (or the rotating shaft)334 and the bottom of the hole 324, and the tip portion 335 of the fixedshaft (or the rotating shaft) 334 is made slidable inside the hole 324of the gap forming member 307 in the E directions with respect to thegap forming member 307. In the case where such an externally threadedportion 382 and an internally threaded portion 363 are used, the volumeof the gap 306 including the gap 383 changes with respect to the housingbody 303 in the relative rotation of the gap forming member 307 in theR1 and R2 directions with respect to the housing body 303. However, ifthe pitchwise dimensions of the externally threaded portion 382 and theinternally threaded portion 363 are made extremely small, thisvolumetric change is extremely small, and can be absorbed by thecompressibility of the silicone-based unvulcanized rubber 4. In thedamper 1 shown in FIG. 40, the silicone-based unvulcanized rubber 4 ismade to undergo return deformation by the relative rotation of the gapforming member 307 in the R1 and R2 directions with respect to thehousing body 303.

1-19. (canceled)
 20. A damper comprising: a pair of members, andsilicone-based unvulanized rubber interposed between said pair ofmembers, said pair of members being disposed in such a manner as to berelative rotationally movable with respect to each other, saidsilicone-based unvulcanized rubber having a degree of plasticity of notless than 30 and not more than 420 as measured with the Williamplastometer, and relative rotationally moving energy between said pairof members being absorbed through the plasticity deformation of saidsilicone-based unvulcanized rubber.
 21. The damper according to claim20, wherein said silicone-based unvulcanized rubber has a degree ofplasticity of not less than 60 and not more than
 320. 22. The damperaccording to claim 20, wherein said silicone-based unvulcanized rubberhas a degree of plasticity of not less than 160 and not more than 320.23. The damper according to claim 20, wherein at least one of said pairof members has an uneven surface in contact with said silicone-basedunvulcanized rubber, and said uneven surface prevents the slippage ofsaid silicone-based unvulcanized rubber in a vicinity of said unevensurface in the relative movement of said pair of members.
 24. The damperaccording to claim 20, wherein at least one of said pair of members has,on a surface thereof in contact with said silicon-based unvulcanizedrubber, one of a projection and a groove extending in a directionintersecting a direction of the relative movement.
 25. The damperaccording to claim 24, wherein said surface in contact with saidsilicone-based unvulcanized rubber includes a cylindrical surface, andone of said projection and said groove extends substantially parallel toa center line of said cylindrical surface.
 26. The damper according toclaim 24, wherein said surface in contact with said silicone-basedunvulcanized rubber includes one of an annular surface and a disk-likesurface, and one of said projection and said groove extends in a radialdirection of said one of said annular surface and said disk-likesurface.
 27. The damper according to claim 20, wherein said damper is adamper for an automobile seat, and includes: a housing serving as saidone member and having an arm portion and a housing body integral to saidarm portion; and a gap forming member serving as said other member andaccommodated rotatably in said housing body, said gap forming memberforming a gap in cooperation with an inner surface of said housing body,said silicone-based unvulcanized rubber being disposed in the gap, saiddamper being adapted to transmit the rotation of said automobile seat tosaid housing by means of said arm portion, and said gap forming memberbeing adapted to be fixed to a chassis on which said automobile seat isrotatably installed.
 28. The damper according to claim 20, wherein saiddamper is a damper for an automobile seat, and includes: a housingserving as said one member and having an arm portion and a housing bodyintegral to said arm portion; and a gap forming member serving as saidother member and accommodated rotatably in said housing body, said gapforming member forming a gap in cooperation with an inner surface ofsaid housing body, said silicone-based unvulcanized rubber beingdisposed in the gap, said housing being adapted to be fixed by means ofsaid arm portion to a chassis on which said automobile seat is rotatablyinstalled, and said damper being adapted to transmit the rotation ofsaid automobile seat to said gap forming member.
 29. The damperaccording to claim 20, wherein said damper is a damper for an automobileseat, and includes: a housing serving as said one member and having acollar portion and a housing body integral to said collar portion; and agap forming member serving as said other member and accommodatedrotatably in said housing body, said gap forming member forming a gap incooperation with an inner surface of said housing body, saidsilicone-based unvulcanized rubber being disposed in the gap, saiddamper being adapted to transmit the rotation of said automobile seat tosaid housing by means of said collar portion, and said gap formingmember being adapted to be fixed to a chassis on which said automobileseat is rotatably installed.
 30. The damper according to claim 20,wherein said damper is a damper for an automobile seat, and includes: ahousing serving as said one member and having a collar portion and ahousing body integral to said collar portion; and a gap forming memberserving as said other member and accommodated rotatably in said housingbody, said gap forming member forming a gap in cooperation with an innersurface of said housing body, said silicone-based unvulcanized rubberbeing disposed in the gap, said housing being adapted to be fixed bymeans of said collar portion to a chassis on which said automobile seatis rotatably installed, and said damper being adapted to transmit therotation of said automobile seat to said gap forming member.
 31. Thedamper according to claim 27, wherein said housing body has a pluralityof concentric arcuate projections, and said gap forming member has aplurality of concentric hollow cylindrical recessed portions in whichsaid arcuate projections of said housing body are respectively disposedwith the gap therebetween.
 32. The damper according to claim 27, whereina slit extending radially and communicating with the gap is formed insaid gap forming member.
 33. An automobile seat comprising: said damperfor an automobile seat according to claim 27; and a seat providedrotatably on said automobile chassis, the rotation of said seat beingtransmitted to one of said housing and said gap forming member, andanother one of said housing and said gap forming member being fixed tosaid chassis.
 34. The automobile seat according to claim 33, wherein abackrest is rotatably provided on said seat.